The present application is directed to a medical implant, and more particularly, to an expandable medical implant with rotating collars that are positioned within a base.
Various medical surgical procedures use an implant that is positioned within the patient between supporting skeletal structures. One example is an implant positioned between vertebral members of the spine. The spine is divided into four regions comprising the cervical, thoracic, lumbar, and sacrococcygeal regions. The cervical region includes the top seven vertebral members identified as C1-C7. The thoracic region includes the next twelve vertebral members identified as T1-T12. The lumbar region includes five vertebral members L1-L5. The sacrococcygeal region includes nine fused vertebral members that form the sacrum and the coccyx. The vertebral members of the spine are aligned in a curved configuration that includes a cervical curve, thoracic curve, and lumbosacral curve. Intervertebral discs are positioned between the vertebral members and permit flexion, extension, lateral bending, and rotation.
Various conditions may lead to damage of the intervertebral discs and/or the vertebral members. The damage may result from a variety of causes including but not limited to a specific event such as trauma, a degenerative condition, a tumor, or infection. Damage to the intervertebral discs and vertebral members can lead to pain, neurological deficit, and/or loss of motion.
Various procedures include replacing the entirety or a section of a vertebral member, the entirety or a section of an intervertebral disc, or both. One or more replacement implants may be inserted to replace the damaged vertebral members and/or discs. The implants are configured to be inserted into the defect space and contact against the remaining adjacent vertebral members.
The implant may also be used in applications with other skeletal structures. Examples include replacing long bones or portions of appendages such as the legs and arms, or a rib or other bone that is generally longer than it is wide. Examples include, but are not limited to, a femur, tibia, fibula, humerus, radius, ulna, phalanges, clavicle, and ribs.
It may be advantageous for the implants to be adjustable to vary one or more dimensions. The adjustability may ensure that the implants properly accommodate the space between the skeletal structures. The adjustability may also ensure that the implants adequately contact and support the skeletal structures.